alt.hn

3/28/2026 at 1:04:56 AM

Teenage Engineering's PO-32 acoustic modem and synth implementation

 https://github.com/ericlewis/libpo32

by ericlewis

3/31/2026 at 9:56:30 PM

Digital modules from Mutable Instruments (and related clones + offshoots) use audio-based data transfer for firmware updates.

Interesting way to give the consumer the ability to change the firmware without having to access the back of the module (there's a way to use a serial JTAG adapter as well).

https://github.com/pichenettes/mutable-dev-environment?tab=r...

by chabes

3/31/2026 at 10:15:29 PM

As I understand it, transferring data as audio goes back quite ways, right?

I had a Commodore 64 that could use phillips tape. I'm drawing. blank, but IIRC there were musical instruments (maybe the roland juno 60?) in the 80s that were storing their data as audio, too.

by scarecrowbob

4/1/2026 at 11:26:44 AM

Yus, apparently some software was broadcast on the radio, people could record it on tape and use it on their Commodore and such.

by Cthulhu_

4/1/2026 at 3:38:41 PM

Heck, my computer used to get on the land line telephone and ask its friends for software.

One of the weirdest things I did last week was realizing that my flipper zero could be used as a redbox... now I just need to find a payphone with a trunk...

by scarecrowbob

4/1/2026 at 9:30:37 PM

Yep, that's correct about the Juno 60. There are people still sharing WAV files of the original factory patches which is cool to be able to re-load now and again.

by lintbrush

3/31/2026 at 11:53:34 PM

Here, this is a lot of fun.

http://www.whence.com/minimodem/

by somat

4/1/2026 at 1:19:52 AM

I mean, I'm thinking about upgrading from my tech license so I can start playing with digital modes on HF radio...

damn, this thread is making me feel old...

by scarecrowbob

4/1/2026 at 12:02:41 AM

Kansas City Standard was delivered on cheap records through the mail

by bobmcnamara

4/2/2026 at 12:18:32 AM

Disney used it to control their animatronics for many years (aka, "audio animatronics")

by duped

4/1/2026 at 2:27:12 PM

Yeah, Juno-106 as well.

by jvoorhis

4/1/2026 at 2:28:49 PM

On a similar if sillier note note, Korg made a Hatsune Miku guitar effect[1] that was programmable through audio sent from an iPhone app through the guitar pickup.

Annoyingly, the free app isn't available on the US App Store, so open source software would be useful (insofar as the ability to play back a predefined sequence of Vocaloid phonemes using an electric guitar is useful).

[1] https://www.korg.com/us/products/effects/mikustomp/

by jasomill

4/1/2026 at 3:05:31 PM

I have been on the hunt for this pedal, and it is now stupidly expensive. I hope they rerelease it one of these days

by unixnight

3/31/2026 at 9:35:23 PM

Hey ericlewis - this is cool! Can I ask how you figured it out?! Doing this for my PO-33 was on my bucket list. I thought I might have to resort to voltage glitching to get a firmware dump, which is currently beyond my skills.

by socks

4/1/2026 at 8:24:11 AM

Unfortunately I think only a few of the PO's support this transfer method, and I don't think the 33 is one of them. They were never meant to be updated at all, as I understand it.

by svantana

3/31/2026 at 11:52:40 PM

Me too, have been trying to crack this for so long!

by chr15m

4/1/2026 at 1:44:31 AM

I was able to get part way some years ago by demodulating the bitstream with gnuradio and then making small changes (like replacing one note with the next higher one) and noting the differences. So that is one possible, but probably too inefficient way.

I never got close to finishing or publishing anything. Awesome to see this released and I'll have to play with it!

by reerdna

3/31/2026 at 11:47:57 PM

> A user you’ve blocked has previously contributed to this repository.

I see that claude’s been in here as well.

by c-c-c-c-c

3/31/2026 at 11:29:34 PM

I didn't think I'd see something on the PD squad before I saw it on HN!

by nosrepa

3/31/2026 at 7:31:44 PM

That's amazing. I wonder how accurate is the synth engine?

by larme

3/31/2026 at 9:40:33 PM

The synth engine is an implementation of https://soniccharge.com/microtonic Not sure what "accurate" means in your context though?

by smlacy

3/31/2026 at 10:16:42 PM

How closely it replicates microtonic's, would be my assumption

by girvo

3/31/2026 at 8:03:50 PM

> The PO-32 is not receiving finished drum audio when you transfer a sound or a pattern. It receives structured data:

Wait, isn't this what MIDI is for?

by kmeisthax

3/31/2026 at 9:41:54 PM

It's sending sound parameter information (e.g. filter cutoff at 12khz, resonance at 1.6, Q of 0.89) along with note information (e.g. start playing note A4 with velocity 80). You could absolutely use a MIDI CC channel to convey this information. The OP-32 chooses a different route and encodes this into an audio signal so that it can transmit it over the air using the speaker/mic instead of a wireless stack.

I bet it sounds like a dial-up tone!

by itishappy

3/31/2026 at 11:18:55 PM

Would have been easier to say it receives patches - I think most people would get this.

by txbrown

4/1/2026 at 6:46:06 AM

The word "patch" has a naming conflict between the disciplines of synthesizers and software.

by Intermernet

4/1/2026 at 1:54:17 PM

what you mean? synthesisers are software... I think the context is clear here and we're talking about software made for music, so the usage of patch is accurate. If author wanted to use "patch" to mean patching a file they would likely be specific or context could be inferred.

"A patch is data for modifying an existing software resource such as a program or a file"

Which is what patching synths/drum machines (and files) does.

by txbrown

3/31/2026 at 8:26:46 PM

All it means is that the PO-32 is not a sampler, it's a synthesizer, so it receives a "preset" for the synth rather than an audio sample.

by iamjackg

4/1/2026 at 6:39:48 AM

> Wait, isn't this what MIDI is for?

It is but I don’t think this Pocket Operator has MIDI without adding third party hardware.

by Lio

3/31/2026 at 10:55:40 PM

Looking at this I can only think one thing: "Just put USB-C in, the connector is ten cents and it's far more convenient than hipster shit like this, you pretentious fucks"

by PunchyHamster

4/1/2026 at 1:26:05 AM

This was released in 2017 for one thing. Considering that enough people are still interested in it a decade later they probably did something right.

by mobiledev2014

3/31/2026 at 11:03:06 PM

Pretentious hipster shit is their whole brand.

by Gigachad